<!DOCTYPE html>
<html>
<body>

<h1>A Hidden Field (look in source code)</h1>

<form action="https://www.w3schools.com/action_page.php">
  <label for="fname">First name:</label>
  <input type="text" id="fname" name="fname"><br><br>
  <input type="hidden" id="custId" name="custId" value="3487">
  <input type="submit" value="Submit">
</form>

<p><strong>Note:</strong> The hidden field is not shown to the user, but the data is sent when the form is submitted.</p>

</body>
</html>
